The invention relates to a feeding means for intermittently rotating a circular saw blade of great pitch, comprising a slip-on arbor for the saw blade, a principal pawl designed for strokewise reciprocating motion and such as to push the tooth face of a tooth of the saw blade upon every other forward stroke into a working position, a secondary pawl disposed behind the principal pawl and designed to reciprocate together with the principal pawl and such as to engage behind the tooth face of the next tooth upon each return stroke following the positioning of a tooth and to move said tooth face during the next successive forward stroke into an intermediate position at which the principal pawl may engage behind this tooth face during the subsequent return stroke, and a stop which limits the catch movement of the secondary pawl.
A known feeding means of this kind (DE-PS 689 015) has the secondary pawl supported pivotably on a slide which is guided for displacement in longitudinal direction and adapted to be clamped in position by an attachment screw. The secondary pawl is spring loaded in the direction of its catch movement, the stop limiting this catch movement being formed by a setscrew threaded into the slide. At each defined adjustment of this setscrew, the secondary pawl moves on a drag curve during the movement of advance of the saw blade caused by it, the drag curve depending on the path of movement of the principal pawl taking place simultaneously. It is difficult, and in some cases impossible, to determine this path of movement of the principal pawl and the adjustment of the stop for the secondary pawl such that the secondary pawl will abut invariably at a predetermined location of the respective tooth face it is pushing ahead. Consequently, the secondary pawl travels along the tooth face which thus may become damaged and reach a position at the end of the forward motion of the secondary pawl, not entirely corresponding to the intended intermediate position. Hereby the subsequent catching of the principal pawl may be disturbed.
In another known feeding means for intermittently rotating a circular saw blade (DE-PS 3 048 738) a guide device which is pivotable about the axis of an arbor for a saw blade carries a pawl bearing at an adjustable distance from said axis, a feeding pawl being supported by said bearing. As there is no second feeding pawl, the problems discussed above do not occur.
It is, therefore, an object of the invention to avoid the risk of troubles of the kind described in a feeding means of the kind specified initially.